Chuck



Aug- 7, l934 R. s. BRowN 1,969,687

CHUCK` Original Filed April l. 1926 A INVENTOR ATTORNEYQS.

Patented Aug. 7, 1934 'PATENT OFFICE L pNl'rED STATES cnUcx Original application April V1926, Serial No. 98,974. Divided and this application October 1,l

1926, serial 1931 f No. 138,852. Renewed'October 6,

2o Claims. (01.279-4-7112) MyY invention relates to a chuck particularly, though not exclusively, adapted for use in connectii'm` with an automatic chucking machine employing a plurality of similar chucks. This application is a division of my co-pending application, Serial No. 98,974, filed April 1, '1926, as to the matter shown in Figs. 1 to 4 of rthe drawing. K ,10 Among the objects of the invention are:

operatedeither manually or by power means, andin which the chuck jaw opening may be relativelyV ,large to 'accommodate work pieces of 1,. irregular form; to provide` a chuck having means o' for exertinga variable pressure between the chuck jaws upon the application of a substantiallyuniformvforce to a part of said means; and, in general, to provide an improved form of chuck for securely holding small ,work pieces. Briejy` stated, in the `preferredform of the invention I employ. two chuck jaws` movable relatively to each other for chucking and unchucking a ,work article. These jaws may be moved byjsuitable means Vsuch .as a screw. I may employ power means for rotating thescrew, and means preferablyin the'form of gearing is interposed between the power meansvand the screw for causing the latter Ato exert a vvariable force upon the chuck` jaws upon the applica- 'tion of a substantially 4uniform force to a part ofsaid means. ASuch gearing may include eccentrically mounted intermeshing gears.

In the drawingrwhich shows, for illustrative purposes only, a preferred form of the invention-r Y ,.Fig. 1 is a `view .in end 'elevation of a turret having four chucks thereon;

Fig. 2 vis an enlarged View in'end of one chuck shown in Fig. 1; '40;' Fig. 3 is a sectional view taken substantially in,I the planey of the line 3-3 of Fig. 2;

41s a plan .view of thechuckshown in Fig. 3 with acoverplate removed;

Fig. 5 shows-a plan and a sectional view of `a detail i elevatlon .In` said drawing, o indicates a turret which` may carry1 a .plurality of (injthis case four) chucks 6-f6. While the invention will be described as embodied in, and as particularly applicableto, lan automatic 'chucking machine,

wherein a plurality of similar chucks are employed on a turretV which may be indexed to present work articles in the respective Vchucks successively-to tools, it is to be understoodY that thefprinciple's of the `invention 'are of broader' To provide an improved chuck, which may be,

application. .and I do not wish to `be limited to the particular use to which the improved chuck is to` be put.

The chuck includes a body 7, which may be secured to a turret 5. 8-8 indicate two chuck jaws, which may be moved relatively to each other. In the form shown, both jaws are mov-` able, and for the purpose of moving these jaws I may employ a right and left hand threaded screw Y9, which maybe held against longitudinal movement on the body 7 as by means of an abutment fork 10. False jaws or pads 11-11 may be secured to the jaws 8 8 as by means of screws `l2-l2.V The `false jaws may be made so as to conform to thecontourof the particular work article 13 to be gripped. The screw 9 may be provided with a suitable tool receiving part 14. foroperating the rchuck jaws manually when tooling up for any particular work article. It will be clear that, by`rotating the screw 9 in one direction, the `jaws will be separated, and on rotating thescrew in the opposite direction,V the jaws will be movedtoward each other to gripping position. f

The chuck is arranged to be actuated by. power means. In the `form shown,- I employfa shaft 15 journaled in the chuckbody and provided at one end with a pinion`l6, lwhich may be power driven asby means oi a rack 17. The rack may be guarded by any suitable form of housing 17. As will be readily understood, the rack 177 mayf be connected ,to suitable power drivenmeans, such as Ato a fluid actuated piston orthe like. The shaft 15 serves to rotate the screw 9 through-suitablermeans for imparting a variable force to the screw upon the application of y a substantially uniformI force tothe shaft 15. In the particular embodiment shown, 1 employ an elliptical gear 18k secured` uponthe shaft l5, and this elliptical gear meshes witha corresponding elliptical gear 19 secured yupon the screw 9. 'With the elliptical gears in the positions shown in Figs. 3 and4, the chuck jaws will be separated and rotative movement of the gear 18 will rotate the gear 19 at its fastest speed but with the smallest leverage. With the elliptical gears 18-19 rotated 180 from the positions shown in Figs. 3 and 4, movementV of the gear 19 will -be at the slowest rate, but the rotative force transmitted tothe gear 19 will be. the maximum. I therefore arrange the spacing of the jaws or the false jaws, and key the gears so that the work article 13 Awill be gripped when thezelliptical gears have ybeen rotated substantially 180 from the positions shown in the drawing. It will therefore be seen that a substantially uniform force applied to the shaft 15 through ,the pinion 16 andv rack 17 will transmit a variable force to the elliptical gear 19;and operating screw 9, and the work article 13 may be gripped much more securely thanif the force of the rack 17 were transmitted to the chuck jaws in a uniform manner. n

While the parts may be so proportioned that most work articles may beinserted between the jaws after less than halffamrevolution o'ffthe elliptical gears 18-19, it rwill be plainthatone or more complete revolutions of the elliptical gears could be effected so as to get a .very wide opening between the jawsQjItisfhowever,` de`- in the positions substantially 180 fromAthose shown in Figs. 3 and 4 at the time the work article is finally gripped. By such proportioning of the parts, the maximum effect of the increased'gripping action of the present chuck Vis" As above explained, it is advantageous toisov kposition and proportion theparts that the chuck jaws will be in gripping engagement with the work articleA when the elliptical gears are rotated substantially 180 yfrom the positions shown in Figs. 3 and 4. In order to facilitate proper positioning of the elliptical gears t'o attain that result, I may provide means for permitting the elliptical gears or one of them to be held at various angular positions relatively to their shafts and yet .be securely held thereon. Such a means is illustratedY in Fig. ,5 wherein the square hole 20 is positioned in a.'predeter` mined definite angular position in the gear 19. With the hole-positioned so-that a perpendicular to one of the iiat sides extends at an angle of 671/2 to the major 'axis of the ellipse, eight different equally spaced angular positions of the gear 19 on the screw or shaft 9 may ibe obtained. It will be clear that, by removing the retaining nut and lifting the gear 19 off of the square shank on the screw 9 and again replacing the gear after rotating the same 90, 180 `or 270, four equally spaced angular positionsv of the gear may beobtained. `By making the gear invertible, the'latter may be removed from the squared portion onthe shaft and inverted, in

gear on the shaft` 9 may be obtained.` By inclining the square hole inthe gear as indicated in Fig. 5, the corresponding positions of the gear when face 'up' and when inverted, will be `45" from each other. Therefo'rathe four possible positions with the gear face up'will be at an angle V of 45 to the corresponding four possible positionsfwith the gear inverted. Therefore, eight equally spaced angular positions of the gear on the shaft are possible. By making al hole having any other number ofv sides, the number of angular positions possible to obtain may be made equal to twice the number of fiat sides of one of the interfitting angular portions, and by positioning the angular hole at the proper angle tothe major axis of the ellipse, these various positions may be spaced at equal angles t0 each other.' By this means, therefore, the gear will always be held securely on the screw, and yet a comparatively large number of possible angular positions maybe had so as to have the gears most advantageously positioned for gripping the work article as above described. It maybe desirable to change the poe.

sitions of both gears on their respective shafts `Selliptical I mean to include such other forms.

`While the invention has been described in detail and one specific form illustrated, I do not wish to belimited to the specific embodiment shown, nor tothe particular agencies for carrying the invention into effect, for changes may be made within the scope of the invention as defined in theappended claims.

v '."I`claixn: sirable that the elliptical-,gears"shalljnally be,

f .1-.'In a .,chuck, afchuck body, a plurality of chuck jaws, and means including a pair of intermeshing gears each having teeth at different distances from the axes of rotation of said gears for moving4 said jaws` toward each kother with a variable force upon the application of a uniform force to one of said gearsf'v f 2. In a chuck, a chuck bo'dyQa plurality "of,

chuckjaws, means for moving said jaws relatively to .each other, including a pair of meshing elliptical gears, and 'meansffor driving one of said gears rwhereby said jawsiwill be moved with a Yvariable force upon the application of a substantially uniform force to one of said elliptical gears.

A3. In a chuck,` a chuck body, a. plurality 'of jaws therein, screw means for moving said jaws relatively to each other, and lmeans including meshing elliptical gears for rotating saidjgscrevv means whereby said screw means will be `moved with ya :variable force upon the application of a substantially uniform force to one of saidrellipticalgears.

4. In a` chuck, a chuck` 4 body, la plurality fof jawsvcarr'ied thereby, means including meshing eccentrically mounted gears for moving, said jaws relatively to each other, a spurgearconnected toone of said eccentrically" mounted gears, and means for 'rotating saidspur` gear for causingjsaid eccentrically mounted' gears'lito rca tate'and move said c huck jaws.

f5. In a chuck, a chuck body,A a p'luralityoil chuck jaws, meanslincludingI `elliptical gears for moving' said jawsv relativelyto each other, and rack pinion means for rotating oneoffsaid elliptical gearsfor causing said chuckwjawsuto be'actuated thereby. Y ,i

' 6'. In a`j.chucka1chuck body,` lay plurality of jaws carried thereby, a right andleft lhanded screw for movingvsaid chuck jaws, an 4elliptical gear carried by saidV screw,v a second ellipticalr gear meshing with said rst mentioned el1ipti' cal gear and held 4on ashaft journaled in'fsaid chuck body, a pinioncn said'shaft, and a rack for rotating said' pinion. n

7. In a chuck, achuck body, a plurality :of

chuck jaws, Vmeans, -forfmovingMsaid'ja'ws rela,-` tively to each other, elliptical gears for moving said means, said means having :nat portions, one, of said gears being invertible and havingvint'er# fitting fiat portions, said flat 'portionsfnf said4 elliptical gearbeing positioned at 4,deiinite angles tothe major axis of said elliptical gear, whereby*v `145 flat portions in a number-,of substantially equi'-VJ saidgear maybeV held-onM said means. by said distant angular positionsk equalr to-` twice the member of'vflat portions on one fof. said members.A

f8; In a chuck, -achuckc body, .Bf plurality of chuck jaws, means for moving-said jaws relaf` tively to each other, elliptical gears for moving said means, said means and one of said gears having squared intertting parts for holding said gear on said means, said squared part on said velliptical gear being positioned so that a perpendicular to one of the ilat sides of said squared portion lies at an angle of about 671/2 to the major axis of said elliptical gear.

9. In a chuck, a chuck body, a plurality of chuck jaws, screw means for moving said jaws relatively to each other, said screw means having a square shank thereon, elliptical gears for moving said screw means, one of said gears having a square hole to be received on said square shank for definitely positioning said screw means and said elliptical gear relatively to each other, said square hole in said elliptical gear being positioned so that a perpendicular to one of the flat sides of said square hole extends at an angle of about 671/2 to the major axis of said elliptical gear.

l0. In a chuck, a chuck body, a plurality of chuck jaws, and means for moving said jaws relatively to each other including a rack and gear with teeth at different distances from its center of revolution, whereby a uniform force applied to said rack will exert a variable force on said jaws through said gear.

11. In a chuck, a chuck body, a plurality of chuck jaws, means for moving said jaws relatively to each other, including a gear with teeth at different distances from its center of revolution, and means for actuating said gear, whereby said gear will exert a variable force for moving said jaws upon the application of a uniform force thereto.

12. In a chuck, a chuck body, a plurality of chuck jaws for gripping a work article, actuating means or moving said jaws relatively to each other, operating means connected to said actuating means and including a toothed member having teeth at different distances from its axis of revolution, whereby a uniform force applied to the teeth of said toothed member will cause said member to exert a variable force for moving said jaws.

13. In a chuck, a chuck body, a plurality of chuck jaws, actuating means for moving said jaws relatively to each other, operating means for said actuating means, said operating means including a gear having teeth at different distances from its axis of revolution, said gear being invertible, and intertting parts on said gear and a part or said means for holding said gear in definite angular positions whereby said gear may be held in a number of different angular positions for the purpose described.

14. In a chuck, a plurality of gripping members, and means for moving the same relatively to each other including a rotatable member and a variable leverage means for rotating said rotatable member with a variable force upon application oi a uniform actuating force to said variable leverage means, said variable leverage means and rotatable member being constantly cooperatively articulated, whereby said gripping members will be moved by the same forceV each time they reach a predetermined position.

15. In a chuck, a plurality of gripping members, a rotary member for moving a plurality or said gripping members and means for imparting a variable force to said rotary member upon application of a uniform actuating force, said means and said rotary member being constantly cooperatively articulated, whereby said gripping members will be moved by the same force each time they reach a predetermined position.

16. In a chuck, a chuck body, a plurality of chuck jaws, rotary means for moving said jaws relativelyv to each other, and gearing of varying ratio to operate the rotary means relatively rapidly and with low torque during the idle portions of chuck jaw movement and relatively slowly and with high torque when the jaws are engaging with Work, said rotary means and gearing being constantly cooperatively articulated, whereby said jaws will be moved at the same speed each time they reach a predetermined position.

17. In a chuck, a chuck body, a plurality of chuck jaws, rotary means and gearing of varying ratio for opening and closing the jaws with relatively low torque during one part of the jaw movement and with relatively high torque during another portion of the jaw movement, said rotary means and gearing being constantly cooperatively articulated, whereby said jaws will be moved at the same speed each time they reach a predetermined position.

18. In a chuck, a chuck body, a plurality of jaws, rotary means including gearing of varying ratio carried with said chuck body for causing the jaws to operate relatively rapidly during the idle portion of their movement and relatively slowly when engaging with work, said rotary means and gearing being constantly cooperatively articulated, whereby said jaws will be moved at the same speed each time they reach a predetermined position.

19. In a chuck, a rotary actuating member, a plurality oi jaws actuated by said rotary actuating member, and gear means by which the torque applied to said actuating member is progressively increased during a part of the chuck jaw movement.

20. In a chuck, a rotary jaw actuating member, a first gear means for actuating said member, a second gear means for actuating said rst gear means, one of said gear means including variable speed gearing for progressively increasing the torque applied to said rotary jaw actuating member during a part of its rotary rmovement.

ROBERT S. BROWN. 

